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41.
Hepatocellular carcinoma (HCC) and colorectal carcinoma with hepatic metastases (mCRC) are cancers with poor prognosis and limited therapeutic options. New approaches are needed and adoptive immunotherapy with Vγ9Vδ2 T lymphocytes represents an attractive strategy. Indeed, Vγ9Vδ2 T cells were shown to exhibit efficient lytic activity against various human tumor cell lines, and in vitro Vγ9Vδ2 T expansion protocol based on single phosphoantigen stimulation could be easily performed for healthy donors. However, a low proliferative response of Vγ9Vδ2 T cells was observed in about half of the cancer patients, leading to an important limitation in the development of Vγ9Vδ2 T cell-based immunotherapy. Here, for the first time in the context of cancer patients, Vγ9Vδ2 T cell expansions were performed by co-culturing peripheral blood mononuclear cell (PBMCs) with autologous dendritic cells (DCs) pretreated with aminobisphosphonate zoledronate. For patients not responding to the conventional culture protocol, co-culture of PBMC with zoledronate-pretreated DCs induced strong cell expansion and allowed reaching a minimal rate of purity of 70% of Vγ9Vδ2 T cells. The potent immunostimulatory activity of zoledronate-treated DCs was associated with higher amount of isopentenyl pyrophosphate (IPP) in the culture and was correlated with better ability to activate Vγ9Vδ2 T cells as measured by IFN-γ production. Moreover, we demonstrated that the cytotoxic level of Vγ9Vδ2 T cells against freshly autologous tumor cells isolated from patients could be significantly increased by pretreating the tumor cells with zoledronate. Thus, this method of generating Vγ9Vδ2 T cells leads eligible for Vγ9Vδ2 T cell adoptive immunotherapy the HCC and mCRC patients.  相似文献   
42.
Carbon dioxide is released from the soil to the atmosphere in heterotrophic respiration when the dead organic matter is used for substrates for soil micro-organisms and soil animals. Respiration of roots and mycorrhiza is another major source of carbon dioxide in soil CO2 efflux. The partitioning of these two fluxes is essential for understanding the carbon balance of forest ecosystems and for modelling the carbon cycle within these ecosystems. In this study, we determined the carbon balance of three common tree species in boreal forest zone, Scots pine, Norway spruce, and Silver birch with gas exchange measurements conducted in laboratory in controlled temperature and light conditions. We also studied the allocation pattern of assimilated carbon with 14C pulse labelling experiment. The photosynthetic light responses of the tree species were substantially different. The maximum photosynthetic capacity (P max) was 2.21 μg CO2 s−1 g−1 in Scots pine, 1.22 μg CO2 s−1 g−1 in Norway spruce and 3.01 μg CO2 s−1 g−1 in Silver birch seedlings. According to the pulse labelling experiments, 43–75% of the assimilated carbon remained in the aboveground parts of the seedlings. The amount of carbon allocated to root and rhizosphere respiration was about 9–26%, and the amount of carbon allocated to root and ectomycorrhizal biomass about 13–21% of the total assimilated CO2. The 14CO2 pulse reached the root system within few hours after the labelling and most of the pulse had passed the root system after 48 h. The transport rate of carbon from shoot to roots was fastest in Silver birch seedlings.  相似文献   
43.
Temperature has generally great effects on both the activity and composition of microbial communities in different soils. We tested the impact of soil temperature and three different boreal forest tree species on the archaeal populations in the bulk soil, rhizosphere, and mycorrhizosphere. Scots pine, silver birch, and Norway spruce seedlings were grown in forest humus microcosms at three different temperatures, 7–11.5°C (night–day temperature), 12–16°C, and 16–22°C, of which 12–16°C represents the typical mid-summer soil temperature in Finnish forests. RNA and DNA were extracted from indigenous ectomycorrhiza, non-mycorrhizal long roots, and boreal forest humus and tested for the presence of archaea by nested PCR of the archaeal 16S rRNA gene followed by denaturing gradient gel electrophoresis (DGGE) profiling and sequencing. Methanogenic Euryarchaeota belonging to Methanolobus sp. and Methanosaeta sp. were detected on the roots and mycorrhiza. The most commonly detected archaeal 16S rRNA gene sequences belonged to group I.1c Crenarchaeota, which are typically found in boreal and alpine forest soils. Interestingly, also one sequence belonging to group I.1b Crenarchaeota was detected from Scots pine mycorrhiza although sequences of this group are usually found in agricultural and forest soils in temperate areas. Tree- and temperature-related shifts in the archaeal population structure were observed. A clear decrease in crenarchaeotal DGGE band number was seen with increasing temperature, and correspondingly, the number of euryarchaeotal DGGE bands, mostly methanogens, increased. The greatest diversity of archaeal DGGE bands was detected in Scots pine roots and mycorrhizas. No archaea were detected from humus samples from microcosms without tree seedling, indicating that the archaea found in the mycorrhizosphere and root systems were dependent on the plant host. The detection of archaeal 16S rRNA gene sequences from both RNA and DNA extractions show that the archaeal populations were living and that they may have significant contribution to the methane cycle in boreal forest soil, especially when soil temperatures rise.  相似文献   
44.
45.
The purpose of this study was to evaluate residential short term "spot" measurements as surrogates for long term personal magnetic field (MF) exposure. In an epidemiological study on birth weight and pregnancy delay, MF exposure was assessed by taking five spot measurements in each room. For a subsample of 30 subjects 24 h personal MF measurements were made, and the following exposure metrics were calculated: 24 h arithmetic mean, 24 h median, percentage of time above 0.15 microT, and percentage of time above 0.29 microT. The 24 h exposure metrics were used as gold standards, when evaluating the validity of various summary measures calculated from spot measurements for assessing personal exposure. Based on Spearman correlation coefficient (r), specificity and sensitivity, the average of the spot measurements of a residence resulted in least exposure measurement error (misclassification). Also the above bed spot value correlated better with the 24 h metrics than any room average. Spot measurements performed about equally well in predicting different types of exposure metrics.  相似文献   
46.
47.
17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) converts the potent estrogen estradiol into the weakly active keto form estrone. Because of its expression in bone, inhibition of 17β-HSD2 provides an attractive strategy for the treatment of osteoporosis, a condition that is often caused by a decrease of the active sex steroids. Currently, there are no drugs on the market targeting 17β-HSD2, but in multiple studies, synthesis and biological evaluation of promising 17β-HSD2 inhibitors have been reported. Our previous work led to the identification of phenylbenzenesulfonamides and -sulfonates as new 17β-HSD2 inhibitors by ligand-based pharmacophore modeling and virtual screening. In this study, new molecules representing this scaffold were synthesized and tested in vitro for their 17β-HSD2 activity to derive more profound structure-activity relationship rules.  相似文献   
48.
Estimates of regional and global freshwater N2O emissions have remained inaccurate due to scarce data and complexity of the multiple processes driving N2O fluxes the focus predominantly being on summer time measurements from emission hot spots, agricultural streams. Here, we present four‐season data of N2O concentrations in the water columns of randomly selected boreal lakes covering a large variation in latitude, lake type, area, depth, water chemistry, and land use cover. Nitrate was the key driver for N2O dynamics, explaining as much as 78% of the variation of the seasonal mean N2O concentrations across all lakes. Nitrate concentrations varied among seasons being highest in winter and lowest in summer. Of the surface water samples, 71% were oversaturated with N2O relative to the atmosphere. Largest oversaturation was measured in winter and lowest in summer stressing the importance to include full year N2O measurements in annual emission estimates. Including winter data resulted in fourfold annual N2O emission estimates compared to summer only measurements. Nutrient‐rich calcareous and large humic lakes had the highest annual N2O emissions. Our emission estimates for Finnish and boreal lakes are 0.6 and 29 Gg N2O‐N/year, respectively. The global warming potential of N2O from lakes cannot be neglected in the boreal landscape, being 35% of that of diffusive CH4 emission in Finnish lakes.  相似文献   
49.
Anaerobic acetate degradation at 70°C and at 55°C (as a reference) was studied by running laboratory upflow anaerobic sludge blanket (UASB) reactors inoculated with mesophilic granular sludge. In UASB reactors fed with acetate-containing media (3 g of chemical oxygen demand [COD] per liter, corresponding to 47 mM acetate) approximately 50 days was needed at 70°C and less than 15 days was needed at 55°C to achieve an effluent COD of 500 to 700 mg/liter. In the UASB reactors at both 70 and 55°C up to 90% of the COD was removed. Batch assays showed that sludges from two 70°C UASB reactors, one run at a low effluent acetate concentration and the other run at a high effluent acetate concentration, exhibited slightly different responses to temperatures in the range from 37 to 70°C. Both 70°C sludges, as well as the 55°C sludge, produced methane at temperatures of 37 to 73°C. The 55°C sludge exhibited shorter lag phases than the 70°C sludges and higher specific methane production rates between 37 and 65°C.  相似文献   
50.
The genetic relationships among New and Old World coregonid fishes were studied by electrophoresis. The genetic composition of 60 populations, representing perhaps nine commonly recognized species of Coregonus and Stenodus from Europe and North America was determined for 37 genetic loci. Six distinct genetic groups were evident. The first contained only populations of the inconnu, Stenodus leucichthys (Güldenstadt). The Nei genetic distance between Stenodus and Coregonus was 0.305, a relatively small value as compared to other salmonid inter-generic comparisons. The second genetic grouping contained the Arctic cisco, C. autumnalis (Pallas), the N. American lake cisco, C. artedii Lesueur, and the Irish pollan, C. autumnalis pollan Thompson. These three taxa appear to be conspecific on the basis of genetic distances. The third genetic grouping contained the European whitefish, C. lavaretus (L.), and the N. American lake whitefish, C. clupeaformis (Mitchill). European and lake whitefish may be conspecific. Lake whitefish from northwestern N. America were more closely related to European whitefish (genetic distance 0.038) than to lake whitefish from central N. America (genetic distance 0.098). The fourth group contained the broad whitefish, C. nasus (Pallas), which is perhaps more closely related to the European/lake whitefish groups than other coregonids. The fifth genetic grouping contained only the Asian endemic, C. peled (Gmelin), and the sixth contained the least cisco, C. sardinella Valenciennes, and vendace, C. albula (L.), which also appear to be conspecific. The widespread genetic groupings obtained for ciscoes indicate that they do not constitute a single closely related group within the genus Coregonus.  相似文献   
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